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Toxicodendron radicans

Toxicodendron radicans known as eastern poison ivy or poison ivy, is a poisonous Asian and Eastern North American flowering plant in the genus Toxicodendron. The species is well-known for causing urushiol-induced contact dermatitis, an itchy and sometimes painful rash, in most people who touch it; the rash is caused by a clear liquid compound in the plant's sap. The species is variable in its appearance and habit, despite its common name, it is not a true ivy, but rather a member of the cashew and pistachio family. T. radicans is eaten by many animals, the seeds are consumed by birds, but poison ivy is most thought of as an unwelcome weed. It is a different species from western poison ivy, Toxicodendron rydbergii, which has similar effects. Numerous subspecies and/or varieties of T. radicans are known, which can be found growing in any of the following forms. R. subsp. Barkleyi Gillis T. r. subsp. Divaricatum Gillis T. r. subsp. Eximium Gillis T. r. subsp. Hispidum Gillis T. r. subsp. Negundo Gillis T. r. subsp.

Pubens Gillis T. r. subsp. Radicans T. r. subsp. Verrucosum GillisThe deciduous leaves of T. radicans are trifoliate with three almond-shaped leaflets. Leaf color ranges from light green to dark green, turning bright red in fall; the leaflets of mature leaves are somewhat shiny. The leaflets are 3–12 cm long up to 30 cm; each leaflet has a few or no teeth along its edge, the leaf surface is smooth. Leaflet clusters are alternate on the vine, the plant has no thorns. Vines growing on the trunk of a tree become attached through numerous aerial rootlets; the vines develop adventitious roots. The milky sap of poison ivy darkens after exposure to the air; the urushiol compound in poison ivy is not a defensive measure. It is eaten by animals such as deer and bears. T. radicans spreads either vegetatively or sexually. It is dioecious; the yellowish- or greenish-white flowers are inconspicuous and are located in clusters up to 8 cm above the leaves. The berry-like fruit, a drupe, mature by August to November with a grayish-white colour.

Fruits are a favorite winter food of other animals. Seeds are spread by animals and remain viable after passing through the digestive tract. T. radicans grows throughout much of North America, including the Canadian Maritime provinces, Ontario and all U. S. states east of the Rocky Mountains, as well as in the mountainous areas of Mexico up to around 1,500 m. Caquistle or caxuistle is the Nahuatl term for the species, it is found in wooded areas along edge areas where the tree line breaks and allows sunshine to filter through. It grows in exposed rocky areas, open fields, disturbed areas, it may grow as a forest understory plant. The plant is common in suburban and exurban areas of New England, the Mid-Atlantic, the Southeastern United States; the similar species T. diversilobum and T. rydbergii are found in western North America, T. orientale in Taiwan, Japan and Sakhalin. T. radicans grows at altitudes above 1,500 m, although the altitude limit varies in different locations. The plants can grow as a shrub up to about 1.2 m tall, as a groundcover 10–25 cm high, or as a climbing vine on various supports.

Older vines on substantial supports send out lateral branches that may be mistaken for tree limbs at first glance. It grows in a wide variety of soil types, soil pH from 6.0 to 7.9. It is not sensitive to soil moisture, although it does not grow in desert or arid conditions, it can grow in areas subject to seasonal brackish water. It is more common now than; the development of real estate adjacent to wild, undeveloped land has engendered "edge effects", enabling poison ivy to form vast, lush colonies in these areas. It is listed as a noxious weed in the US states of Minnesota and Michigan and in the Canadian province of Ontario. Outside North America, T. radicans is found in parts of China. Poison ivy is sensitive to carbon dioxide levels benefiting from higher concentrations in the atmosphere. Higher carbon dioxide levels increase the rate of plant growth, causes them to produce more unsaturated urushiol, which causes stronger reactions in humans. Poison ivy's growth and potency has doubled since the 1960s, it could double again once carbon dioxide levels reach 560 ppm.

Urushiol-induced contact dermatitis is the allergic reaction caused by poison ivy. In extreme cases, a reaction can progress to anaphylaxis. Around 15 to 25 percent of people have no allergic reaction to urushiol, but most people have a greater reaction with repeated or more concentrated exposure; the rash from the urushiol oil lasts about five to twelve days, but in extreme cases it can last a month or more. Over 350,000 people are affected by urushiol annually in the United States; the pentadecyl catechols of the oleoresin within the sap of poison ivy and related plants causes the al

James Ramsay (painter)

James Ramsay was a British portrait painter, working in oils. Ramsay was born in Sheffield, where his father Robert Ramsay was an artisan and dealer, who took on Francis Chantrey as apprentice in 1797. Robert Ramsay published some engravings by John Raphael Smith. While still a youth, James Ramsay was painting professionally in the family business, exhibited at age 17. Ramsay died, after a protracted illness, at 40 Blackett Street, Newcastle-upon-Tyne, on 23 June 1854, aged 68. Ramsay's name first appeared in the catalogue of the Royal Academy exhibition for 1803, when he sent a self-portrait. Three years he exhibited a portrait of Henry Grattan, in 1810 one of John Towneley. In 1811 his contributions included portraits of the Earl of Moira and Lord Cochrane, in 1813 that of Lord Brougham, whom he again painted in 1818. In 1814 Ramsay sent to the academy two scriptural subjects, Peter denying Christ and Peter's Repentance, in 1819 views of Tynemouth Abbey and of North and South Shields, but his works were portraits.

There are at least three by him of Thomas Bewick. A portrait by him of Charles Grey, 2nd Earl Grey, painted for the Literary and Philosophical Society of Newcastle-upon-Tyne, in Newcastle town hall, was exhibited in 1837, together with that of Dr Thomas Elliotson, which went to the Royal College of Physicians, his portrait of Henry Grattan, passed down in the Grattan family, was engraved in mezzotint by Charles Turner, a copy of it by Sir Thomas Alfred Jones went to the National Gallery of Ireland. Ramsay exhibited scriptural and fancy subjects at the British Institution, including Isaac blessing Jacob, in 1813, The Trial of King Charles the First, in 1829, The Entry of the Black Prince into London, in 1841. About 1847 Ramsay left London for Newcastle-upon-Tyne, but he continued to exhibit at the Royal Academy, where he had another portrait of himself in 1849, he was successful, painted portraits of members of Lord Clifford's family, James Northcote, Dionysius Lardner, many others. Ramsay's works are represented in many museums and galleries around Britain, with at least 25 portraits in public collections.

National Portrait Gallery: oil of Thomas Bewick. National Railway Museum, York: oil of Michael Longridge. Attribution This article incorporates text from a publication now in the public domain: Lee, Sidney, ed.. "Ramsay, James". Dictionary of National Biography. 47. London: Smith, Elder & Co

Japanese Society (book)

Japanese Society is an analysis of the structure of Japanese society, written by Nakane Chie. The main theme of the book is the working of what Nakane calls "the vertical principle" in Japanese society, a series of social relations between two individuals, one of whom is senior and one of whom is junior. Nakane formulates the criteria of'attribute' and'frame' to illuminate that way that groups are formed in Japan, to compare Japan with other countries, her thesis is that'frame', circumstantial and may be "a locality, an institution or a particular relationship which binds a set of individuals into one group, is more important that'attribute', "which may be acquired not only by birth but by achievement", examples of which include "a definite descent group or caste". This situation is contrasted with India; the book is broken down into four chapters: Criteria of Group Formation The Internal Structure of the Group The Overall Structure of the Society Characteristics and Value Orientation of Japanese Man Ingroup Social psychology